Magnetic Permeability
A material property measuring the degree to which a medium supports and concentrates magnetic flux inside itself when subjected to a magnetic field.
Governing formula
μ = B / H = μ_r μ₀, μ₀ = 4π × 10⁻⁷ T·m/A
SI unit
H/m (or T·m/A)
In depth
Relative permeability μ_r expresses permeability relative to vacuum (μ₀). Ferromagnetic materials like soft iron possess high relative permeability (μ_r ~ 1,000–100,000), drastically concentrating magnetic flux lines.
Examples in the real world
Laminated soft iron cores inside inductors and power transformers used to amplify magnetic field density and efficiency.